“While I still have reservations on this, I feel that, in the interest of cooperation, we need to move forward,” Heard said.

Commissioner Tommy Hunter was the lone dissenter.

Afterward, he texted Thomas to explain his vote, saying: "I think the plan of joining MARTA is misguided, but since it is an issue that will persist long after my term on the commission, I think the folks who have to foot the bill should decide."

A new state law requires that, if the contract between MARTA and Gwinnett County isn’t signed before the first of the year, the new regional authority called The ATL, or The Atlanta-region Transit Link Authority,would need to have a say, too. That is another wrinkle that could delay any March referendum.